When police announced that the multiplatinum-selling retro-soul superstar Amy Winehouse had been found dead in her London apartment Saturday, word rippled across the pop-music universe with the speed of an all-points bulletin. Fans mourned with their wallets, sending Winehouse's breakthrough 2006 album, "Back to Black," to the top of the iTunes chart. And the person who will be most deeply affected by her death broke down in tears, collapsed, and was placed on suicide watch behind prison walls.

Blake Fielder-Civil, Winehouse's ex-husband and the great love of her life, has been behind bars since June, serving a 32-month sentence for a bungled daytime burglary and possession of an imitation firearm.

After being informed by prison officials of Winehouse's death, he told The Sun newspaper: "I'm beyond inconsolable...my tears will never dry."

Fielder-Civil's remarks barely begin to hint at the violent, co-dependent nature of his relationship with Winehouse. Over the last half-dozen years, the two carried on what was arguably popular culture's bloodiest, druggiest, least predictable, and most volatile love affair. Their on-again, off-again courtship inspired the glamorous melancholy of Back to Black—evidenced by the title track's drug-referencing, lovesick refrain "I love you much, it's not enough / You love blow and I love puff"—but also a death spiral of addiction, self-mutilation, knock-down, drag-out physical assaults, bad tattoos, and even prison sexting.

Further, Fielder-Civil, 29, seems to have remained Winehouse's muse both in life and death.

When the two began dating in 2005, Winehouse was hardly the rock-around-the-clock femme fatale she would later become. Her look was relatively wholesome, if unremarkable, and her jazzy, neo-soul-inflected debut CD, Frank, had been released to generally favorable reviews in 2003 but fizzled commercially. Enter Fielder-Civil, a high-school dropout and former video-production assistant who introduced Winehouse to hard drugs—he says she demanded to try some after watching him ingest them. "I made the biggest mistake of my life by taking heroin in front of her," he told News of the World in 2008. "I introduced her to heroin, crack cocaine, and self-harming. I feel more than guilty."

Fielder-Civil's influence on Winehouse, 27, also compelled a kind of extreme makeover. She began swooping her inky black hair into the towering beehive that would become her signature and started collecting tattoos, including one of a shirt pocket beneath the word "Blake's" on her left breast.

It was never smooth sailing for the couple, though, and during one of their frequent breakups, Winehouse composed her defining album by channeling the tempestuousness of their relationship into songs.

During a 2007 performance, Winehouse acknowledged Fielder-Civil's part in her creative process this way: "Here is a song I wrote when he left me a couple years ago. I wrote the whole album about it, really. We went on our little separate ways, but then realized that we loved each other. Life's too short."

The two stunned their families by eloping in Miami in 2007. But Fielder-Civil was arrested six months later on assault charges—for attacking a pub landlord—and for then "perverting the course of justice" by attempting to bribe the man $400,000 not to show up in court. Fielder-Civil was sentenced to 27 months in Pentonville Prison while Winehouse continued to sell millions of records around the globe, entering the ranks of pop's top acts.

The following year, the performer showed her devotion to Fielder-Civil in ways both self-destructive and ridiculous. Sweeping the Grammys, Winehouse claimed awards in five of the six categories in which she was nominated, including best new artist, song of the year, and album of the year. While accepting the statuette for album of the year, Winehouse gave her imprisoned spouse an unforgettable and widely lampooned shout-out: "This is to my mum and dad—and for my Blake incarcerated!"

Later in 2008, when Fielder-Civil was admitted to a prison hospital following a suspected heroin overdose, Winehouse appeared in public with a tiny teardrop drawn in eyeliner beneath her left eye. And she shocked a journalist from Spin magazine by carving "I love Blake" on her abdomen with a shard of mirror during an interview.

Of course by then, the two were well acquainted with the steep physical toll their love could take. In 2007, Fielder-Civil and Winehouse were involved in a violent altercation at London's chic Sanderson Hotel that left them covered with blood and bruises. (Winehouse denied her husband had roughed her up, insisting that her injuries were self-inflicted.)

Speaking to The Times of London, Winehouse's father, Mitch, recalled Fielder-Civil's rationale for the pair's self-mutilating ways. "He explained to me that when they're going into [drug] withdrawal, if they cut themselves, it takes away the pain," he was quoted as saying.

But as Winehouse began to publicly unravel—a process characterized by drastic weight loss, tumbling out of bars, punching fans, and embarking on a roundelay of rehab stays—Fielder-Civil morphed into something besides her longtime enabler; he became one of Britain's most reviled men. The perception was that Winehouse's rising toxicity was all his fault.

"I won't let him divorce me," she told Britain's Now magazine. "He's the male version of me, and we're perfect for each other."

In 2009, the couple finally did divorce, however, with Fielder-Civil's attorney reportedly citing "Amy's adultery" as the cause of their split. And although both of them moved on to other partners—Winehouse with a rebound fling on the Caribbean island of St. Lucia, and later actor Reg Traviss, and Fielder-Civil with a mother of two he met at a rehabilitation clinic and to whom he is currently engaged—it seems neither could entirely quit the other.

Earlier this month, Fielder-Civil's fiancée, Sarah Aspin, who gave birth to his child earlier this year, accused Winehouse of attempting to win back the affections of her ex-husband via smart phone. "I've had enough of her thinking she can click her fingers and get him back whenever she wants," Aspin told the The Sun earlier this month. "She phones him when she is really out of it and her texts are even signed off 'your wife.'"

(For her part, Winehouse maintained Fielder-Civil would "sext" her up to 10 times a day.)

Although Fielder-Civil received no compensation from their divorce, financial analysts say there is a possibility that he could inherit Winehouse's fortune, now estimated at between $9.8 million and $32.6 million, unless she explicitly wrote him out of her will.

"In the absence of a will, the surviving spouse will inherit at least the bulk of any estate," Tim Worstall writes in a blog post on Forbes.com. "Only if, and I repeat only if, there was a new will written post-divorce which specifically left the estate elsewhere would Blake Fielder-Civil not be the natural inheritor of Winehouse's estate."

On Saturday, his mother, Georgette Fielder-Civil, told Britain's Daily Star she feared an extreme reaction to the tragedy from her son. "Blake will kill himself," she said. "He won't make it without her. He will be devastated, totally and utterly devastated. He'll go straight back to self-harming. I'll have to ring the prison and he'll have to be put on watch.”

While London police have yet to determine Winehouse's cause of death, multiple sources say the singer went on a drug-and-alcohol binge hours before her pulse stopped. In his exclusive 2008 interview with News of the World, Fielder-Civil indicated he broke off their relationship in order to stop being her enabler—in an effort to short-circuit the substance abuse he feared and that many predicted would ultimately take Winehouse under.

"I have to let her go to save her," he said. "I am not abandoning her. I am doing this out of love."